Concrete form unit



1 l w. A. JENNINGS 2,341,993

7 CONCRETE FORM UNIT Filed Nov. 25, 1940 a Sheets- -sheet 2 a Lrllllllllk IIIWW/ I .N M 9 w INVENTOR.

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' ATTORNEYS.

w. A. JENNINGS CONCRETE FORM UNIT 7 Filed Nov. 25, 1940 3 Sheets-Sheet 3ATIIORNEYS.

Patented Feb. 15, 1944 UNITED STATES PATENT OFFICE CONCRETE FORM UNITWilliam Allen Jennings, Des Moines, Iowa Application November 25, 1940,Serial No. 367,082

Claims. (01. 25-131) My invention relates to that class of forms usedfor making concrete structures in which there is employed a number ofunits detachably connected to define the surface boundaries of thestructure when the concrete is poured.

Another object is to provide an improved type of construction for a formunit which is particularly useful in making units of odd sizes orirregular shapes.

Another object is to provide a form unit which when used in conjunctionwith well-known clamping means will fit tightly at the joints ad.-jacent the surface of the concrete, and thus avoid formation ofupstanding ribs or fins in the surface of the concrete structure.

A further object of my invention is to provide a type of form unit withpunched flanges, in which the perforations punched in the flanges arearranged symmetrically about a center line of the plate.

Still a further object is to provide another type of form unit withperforations uniformly spaced longitudinally of th flange, in which thedistance from a corner of the unit to the center of the firstperforation is the same as the center to center distance of theuniformly spaced perforations.

Another object is to provide form units each having a row ofperforations extendin longitudinally along a flange of the unit, inwhich the distance from the centers of the perforations in the row tothe surface of the unit which bounds the concrete structure is uniform,so that units so constructed may be connected in adjacent relation bycentering means extending through the holes in adjacent flanges on unitsplaced edge to edge.

With these and other objects in view my invention consists'in theconstruction, arrangement and combination of the various parts of mydevice whereby the objects contemplated are attained, and in the methodof making such a device, as hereinafter more fully set forth, pointedout in my claims and illustrated in the accompanying drawings, in which:

Figure 1 is an elevational view of a fragmentary portion of a punchedflange strip used in making my units.

Figure 2 is an exploded perspective View of a form unit showing theelements which enter into the assembly.

Figure 3 is similar to Figure 2, being a perspective view of thefinished assembly.

Figure 4 is an enlarged fragmentary horizontal sectional view taken'onthe line 4-4 of Figure 3.

Figure 5 is a view similar to Figure 4 showing a modified form of flangeconstruction. c

Figure 6 is an exploded perspective view ofa form unit in which theperforations are arranged somewhat differently from those in Figure 2.

Figure '7 is a perspective view showing the relation in which units madeaccording to my invention are assembled.

Figure 8 is a perspective view of portions of adjacent units, showin onestage in the procedure of connecting them by a clamp.

Figure 9 is a sectional view showing the rela tion of the flanges inFigure 8.

Figure 10 is a view similar to Figure .8, showing another stage in theprocedure of connecting the units.

Figure 11 is a sectional view correspondin to Figure 9, showing therelation of the flanges in Figure 10.

Figure 12 is a view corresponding to Figure 9, showing a modified formof a flange construction.

Figure 13 is a view corresponding to Figure 11, showing the modifiedform of flange construction.

Figure 14 is a view corresponding to Figure 9, showing a second modifiedform of flange construction.

Figure 15 is a view corresponding to Figure 11, showing the secondmodified form of flange construction.

Figure 16 is an elevational View of portions of the adjacent edges oftwo units made according to one form of my invention, showing one formof corner construction.

Figure 17 is a view corresponding to Figure 16, but showing another formof corner construction.

In the accompanyin drawings I have used the reference numeral 20 todesignate generally what I refer to in this application as a base plate,which is cut from sheet metal, usually sheet iron,

. to the desired shape and size.

'24 and 25.

The numeral 22 designates a flange member, which according to the methodof my invention is preferably formed from a punched strip of metal, asillustrated particularly in Figure 1. This strip is provided with row ofperforations As indicated in Figure 1, the holes 24 and 26 are uniformlyspaced apartlongitudinally of the flange strip 22, the standard unit ofspacing being indicated by the reference character A.

- The perforations 2B are uniformly spaced from the adjacent edge of theflange strip22,v- In Figures 2 and 3 it will be seen how portions of the"or odd shaped form units.

strip 22, cut to the proper length, are applied to the base plate 20 bywelding or other suitable means, to form a flange which is seen indetail in the sectional view of Figure 4. The spacing of the holes 26from the edge of the flange strip is determined by the fact thataccording to my invention all perforations 26 in a set of form unitsshould. be the same distance from the surface 28 of the base plate 2!](Figure 4) which contacts and forms the boundary of the concrete structure. Th thickness of the plate 29 may be different in different units,inasmuch as the requirements of strength and rigidity make it advisableto use heavier material in larger units. Consequently the distance B (inFigure 1) from the center line of the holes 26 to the adjacent edge ofthe strip 22 is dependent upon the thickness of the plate 20 with whichthe particular strip is to be used, and the dimension B is made suchthat when added to the dimension C (the thickne'ss of plate 29) it willgive a distance D which is uniform for all units. The holes 24 aresimilarly formed in the strip 22 at a distance E from the edgedetermined by the thickness C of the plate 29 with which the strip 22 isto be used, and such that E plus C for all units in the set will be auniform value F.

All the perforations 24 and 26 are of the same size, and preferably ofcircular shape. Therefore when two units made as described are placedwith their flanges adjacent, (see Figure 8) insertion of the tapered pin30 of a clamp 32 through any pair of adjacent holes in the flanges willbring the surfaces 28 of the respective base plates 20 into accuratealignment.

Rectangular units can be made in various sizes, having dimensions whichare multiples of the dii'nension A, the unit of longitudinal spacing ofthe holes. With the uniformly spaced holes, it will be apparent thatmany combinations of units may be connected together, using the clamps32, to make up a panel of practically any dimensions which may berequired in a particular construction job.

\ For maximum interchangeability it is desirable that the units beconstructed with lengths and widths which are integral multiples of thedimension A. The flanges for such a unit are preferably out to lengththrough the transverse center line of a pair of holes 24 and 26. Whenthe flanges so made are attached to the plate, the unit will have on allsides perforated flanges in which the first pair of holes at each corneris spaced from the corner of the unit by a distan'c'e A. Standard unitsso formed can be used to ether in innumerable combinations, since theymay be arranged and combined in any way desired.

Forms somewhat similar to those above described, but with the flangesbent up integrally from the base plate, have been in use, but theireconomical manufacture required the use of tools and jigs which wereconveniently adaptable only for making form units of the standardintegral unit sizes. The manufacture of odd-size or irregularly shapedform units with integral flanges was either impossible or commerciallyimpracticable.

In many concrete structures, however, special conditions give rise torequirements for special My method of assembly, as above described, isadmirably adapted to meet such requirements.

It is only necessary to cut the base plate to shape, out side pieces tolength from the punched flange-strip, and weld the side pieces onto thebase plate to form flanges. The flange strip, as pointed out previously,has its holes spaced transversely to allow for base plates of a giventhickness. If various thicknesses are used for plates of differentsizes, it is necessary to have a stock of flange strip for eachthickness to be used. The economy and simplicity which this proceduremakes possible contributes greatly to the ease and convenience ofbuilding concrete structures with metal form units. Specialarchitectural or ornamental featurees can be provided for at minimumadditional cost.

Many of such odd shaped or such special forms will have dimensions whichare not integral multiples of the standard spacing unit A. It istherefore desirable to arrange the perforations in the flanges in someconsistent manner such that the maximum convenience and utility in theuse of the special form units can be achieved. In Figure 3 isillustrated one type of construction for the flanges which I have foundsatisfactory. It involves selecting one corner of the unit as areference point, preferably a right angle corner such as 44 in Figure 3.From this corner along the two adjacent sides the perforations followthe standard unit spacing, coming "out at the corners 46 and 48 inwhatever manner may be determined by the lengths of the interveningsides. An odd shaped unit formed as described can always be fitted intoa standard panel assembly along the two sides described. In some cases,'oval holes (elongated lengthwise of the flanges) can be employed on oddsides, so that adjacent panels with standard punchings can be fittedflush with either end of the odd side.

A second form of construction for the flange perforations is illustratedin Figure 6. According to this modification the flange is cut in such amanner that its perforations are symmetrical about the transverse centerline of the flange. Where the length of theflan'ge is not an integralmultiple of the perforation spaces, this will ordinarily mean that thedistance from the corner of the unit to the first perforation is not astandard unit. However, a rectangular form unit such as that shown inFigure '6, when the perforations are symmetrically arranged asdescribed, has the advantage that it may be turned end for endinterchangeably, and hence it does not have to be examined "carefully tosee which way it will fit when it is being put in place.

In concrete forms employing units of the general kind here involved, thejoints between units give rise to numerous problems. The units oftenreceive hard use in the field, so that they become slightly bent ordistorted. Also, even units in first class condition may deflectslightly under the stresses resulting when the concrete is poured,particularly when vibration or other impact'ing methods are used. Ifdistortions resulting from such causes are sufficient to bring aboutseparation of the adjacent edges of base plates 29 in an assembly ofform units, the concrete will run into the spaces between the units,making ribs or fins in the surface of the concrete structure whichremainafter the form units are removed. The ribs can be chiseled orground off by abrasive wheels, but this operation obviously involvesadditional expense, and is not entirely satisfactory because the linesin the cement are What run out into the crack between the units, whereasthe coarser aggregates, being unable to pass into the narrow space, areretained. When the rib is chipped or ground away, the

strip of coarser structure is exposed, and does not match the rest ofthe concrete surface.

It will be appreciated, therefore, that 'form units which fit tightly atthe edges under all practical conditions of use, are highly desirable.-

The construction which I have devised for attaining the desired resultis illustrated in Fig-; ures 7-17. It consists principally in arrangingthe flanges 22 on the base plate 20 in such a Way that the free edges 34of the flanges are spaced inwardly from the plane passing through theedge of the base plate and perpendicular to the base plate. With such aconstruction, when two units are placed in adjacent relation, with theirbase plates lying in the same plane, the free edges of the flanges willnormally be somewhat spaced apart, as seen in Figures 9, 12 and 14.These three figures illustrate three various forms of construction whichembody my invention. In Figure 9 the flange 22 is attachedperpendicularly to the base plate 20, but is inset slightly from theedge of the base plate. In Figum 12 the flange 22 is attached to thebase plate flush with the edge of the latter, but is inclined inwardlysomewhat as may be seen in the figure. Figure 14 shows a modifiedconstruction in which the flange 22a is formed integrally with the baseplate 20 by folding the sheet of metal from which the base plate ismade. A reverse fold in the flange gives it additional strength. As inthe Figure 12 form, the flange is inclined in- Wardly.

In all three of the forms illustrated it will be appreciated that whenthe jaws 36 of the clamp 32 are pressed down over the free edges of theadjacent flanges, the flanges will be pulled together. The successivestages of this operation are illustrated in perspective in Figures 8 and10, and in sectional views in Figures 11, 13 and 15. Obviously theimportant result of the clamping is that the base plates 20 are drawntightly together along the line 38. A very firm, secure fit is thusobtained, and with form units constructed as in Figures 9 and 12 theformation of ribs or ridges at the joints is practically eliminated.

With the integrally formed flange of Figure 14, a slight rib will appearin the concrete, because the units must necessarily have slightlyrounded corners at 38. However, the heel or base of the flanges at 38will be held in tight fitting relation so that there will be no seepageof the fines in the concrete mixture. Such a rib as does result withthis type of unit can therefore be ground ofi without exposing a stripof coarser aggregate.

Form units incorporating the inset flange of my invention can be made upin several ways, each having certain advantages. In Figure 7 Iillustrate one form, in which a flange is inset from the edge of thebase plate, as shown in section in Figure 9. Thi'sinset at the attachededge of the flange is continued throughout its length.

In Figure 16 I show a form which would appear in-section like Figure 12or like Figure 14. It consists of a flange which is attached to the baseplate flush with the edge thereof. The flanges at their ends 40 (i. e.,at the corners of the form unit) are perpendicular to the base plate.Intermediate the corners, as at 42, the flanges are inclined inwardly,so that when the units are placed in adjacent relation the flanges arespaced apart at their free edges, in the manner indicated in Figures 12and 14. The advantage of this type of construction is that the tightfitting feature of my invention is obtained by the inclined intermediateportions of the flange, whereas the square corners help to retainadjacent panels in a straight line when they are clamped togetherwithout requiring exceptionally sturdy auxiliary lining means.

Figure 1'7 shows a modified form in which the flanges are attached atthe base plate substantially flush with the edges thereof. The flangesare inclined throughout their length. This type of construction has theadvantage of simplicity I for units of various sizes.

and economy in manufacture. Units of any size can be made convenientlyby affixin a standard strip to the base plate according to the methodabove set out, without any special jigs or fixtures Obviously, however,since the cornersof the units are not square, a. panel assemblyconsisting of a number of units clamped together must be retained in astraight line by auxiliary alignment means such as a wood or metal beamclamped to the various units. The same would also be true of the type ofconstruction illustrated in Figure 7.

The various modified forms shownin Figures 7, 16 and 17 all have thecommon feature that the free edge of the flange, at pointsintermediate'the ends thereof, is inset from the plane passing throughthe edge of the base plate and perpendicular to it. Thus in all theseforms, when the clamp jaws are applied, the flange edges are sprungtogether, and a positive tight fit at the heel of the flange, adjacentthe base plate, is achieved.

Some changes may be made in the details of procedure involved in thepractice of my method, and in the construction and arrangement of theparts of the devices which I have described, without departing from thereal spirit and purpose of my invention, and it is my intention to coverby my claims any variant modes of procedure and any modified forms ofstructure or use of mechanical equivalents which may reasonably beincluded within their scope.

I claim:

1. A concrete form panel consisting of a base plate, upstanding flangesaround the periphery of said base plate, and a row of perforationsextending longitudinally along said flanges, said perforations beinguniformly spaced from the plane of the surface of said base piateopposite said flanges, and said flanges being so shaped that the outeredges thereof, at points intermediate the corners of the panel, areinset from the respective planes perpendicular to the base plate throughthe edge of the base plate, whereas the ends of said flanges, at thecomers of the panel lie in said respective planes.

2. A concrete form unit comprising a flat base plate and a flange onsaid base plate having a plurality of perforations therein, said flangebeing perpendicular at its ends to said base plate, and being inclinedinwardly relative to said base plate at points intermediate its ends.

3. The combination of a pair of form units each comprising a base plateand a flange along one edge thereof, said flange at its ends lying inthe plane perpendicular to the base plate through the edge thereof, thefree edge of the flange, at points intermediate the ends of the flange,being normally inset from the plane perpendicular to the base platethrough the edge thereof, said units being positioned with their flangesin adjacent relation and with their base plates in substantially thesame plane, and clamp means embracing said adjacent flanges intermediatetheir ends and tending to draw the free edges of said flanges together.

4. The combination of a pair of form units each comprising a base plate,a flange along one edge thereof, and a row of perforations formed insaid flange, uniformly spaced longitudinally thereof and uniformlyspaced from the outer surface of said base plate, said flange at itsends lying in the plane perpendicular to the base plate through the edgethereof, the free edge of the flange, at points intermediate the ends ofthe flange, being normally inset from the plane perpendicular to thebase plate through the edge thereof, said units being positioned withtheir flanges in adjacent relation, aligning means extending throughadjacent perforations in said adjacently positioned flanges, and clampmeans embracing said adjacent flanges intermediate their ends andtending to draw the free edges of said flanges together. 7

5. A concrete form unit comprising a base plate having a plurality ofsubstantially straight edges, and an upstanding flange along one of saidedges, the free edge of said flange, at points intermediate the ends ofthe flange, being normally inset from the plane perpendicular to thebase plate through the edge thereof, and the ends of said flange lyingin said plane.

WILLIAM ALLEN JENNINGS.

